Hello
I experienced strange problem with bandwith.
My CentOS 4.3 x86_64 server is a gateway to Internet.
The uplink is 20 Mbps full duplex
Eth card is part of NForce4 chipset, the module is "forcedeth"
As a testing tool we use "iperf" http://dast.nlanr.net/Projects/Iperf/
By test we decide downloda is only 10 Mbps (upload is 18-20 Mbps)
The first suspect was ISP, so we did test in cooperation.
ISP Our site
FreeBSD ========= FreeBSD (ISP test machine)
TCP&UDP down 20 Mbps TCP&UDP up 20 Mbps
TCP&UDP up 20 Mbps TCP&UDP down 20 Mbps
result: link is Ok
The second and final suspect was our gateway:
ISP Our site
FreeBSD ========= CentOS 4.3
UDP down 20 Mbps UDP up 20 Mbps
UDP up 20 Mbps UDP down 20 Mbps
BUT
TCP down 20 Mbps TCP up 20 Mbps
TCP up 10-12 Mbps TCP down 10-12 Mbps
SO: there is an problem with TCP ???
At the time of testing there was NO iptable rules or shaping enabled ...
Where to find? I realy do not know.
Petr Kl?ma
e-mail: qaxi@seznam.cz
On Fri, 31 Mar 2006 15:49:48 +0200 "Petr \"Qaxi\" Kl?ma" <qaxi@seznam.cz> wrote:> Eth card is part of NForce4 chipset, the module is "forcedeth"That would be your primary suspect. Forcedeth is reverse engineered driver for nvidia ethernet and is known to behave strangely. If you can repeat your numbers with nvidia drivers, then look for the cause outsite your machine. -- Jure Pe?ar http://jure.pecar.org/